AVCON RECEIVES FAA SUPPLEMENTAL TYPE CERTIFICATES FOR SPECIAL MISSION BOMBARDIER CHALLENGER 604, 605, AND 650 PLATFORMS

Two new STCs expand The Avcon Special Mission Platforms to include Challenger Aircraft

NEW CENTURY, Kan., June 9, 2026 /PRNewswire/ -- Avcon Industries, Inc., a subsidiary of Butler National Corporation (OTCQX: BUKS) and leading aerospace manufacturer and systems integrator specializing in special mission aircraft modifications, has received two Federal Aviation Administration (FAA) Supplemental Type Certificates (STCs) for the Bombardier Challenger 604, 605, and 650 platforms.

The newly issued Avcon STCs approve the installation of the Avcon fuselage underside rail mounting provisions for sensors and mission equipment (STC No. ST12213CH) and the Avcon fuselage underside-mounted radome (STC No. ST12278CH) on Challenger 604, 605, and 650 aircraft (Type Certificate Data Sheet CL600-2B16).

"We are pleased to extend applicability of the Avcon Special Mission fuselage-mounted rail and radome systems to the Challenger 604, 605, and 650 platforms," said Marcus Abendroth, President of Avcon Industries. "The Challenger platform is widely utilized worldwide for intelligence, surveillance, reconnaissance, maritime patrol, and other special mission applications due to its combination of range, cabin volume, and operational flexibility. The Avcon team worked diligently to secure these certifications, and we appreciate their commitment, expertise, and technical achievement throughout the program."

Similar to the proven functionality of the Avcon Special Mission Rail systems installed on King Air and Caravan aircraft, the Challenger rail provisions are generically designed to support the integration of state-of-the-art mission sensors, including large radar systems and electro-optical/infrared (EO/IR) equipment. The Avcon Special Mission Radome incorporates advanced materials engineered to provide a range of transmissivity characteristics compatible with sophisticated synthetic aperture radar (SAR) systems and other advanced intelligence sensors.

Abendroth added: "These certifications significantly expand the Avcon special mission platform portfolio and position the Challenger 604/605/650 as an attractive option for customers requiring greater range, endurance, payload capacity, and mission flexibility. The Challenger certifications represent another step in the Avcon strategy to expand its portfolio of special mission aircraft modification solutions across multiple aircraft platforms."

For more information about the Avcon Challenger Special Mission modification or other Avcon Special Mission Products, please contact Christian Vila or Kalifa Dieme at Avcon Industries at +1 (913) 780-9595 or visit www.avconindustries.com.

About Avcon Industries, Inc.
Avcon Industries, Inc. provides engineering, structural modification, and systems integration solutions for business and commercial aircraft. The company performs special mission aircraft modifications serving business aviation, search and rescue, atmospheric research, ISR (Intelligence, Surveillance and Reconnaissance), forestry, and air ambulance markets, among others. Avcon is widely recognized for its expertise in regulatory-driven aircraft modifications that expand mission versatility.

Avcon Industries, Inc. is a wholly owned subsidiary of Butler National Corporation (OTCQX: BUKS), a publicly traded company headquartered in Olathe, Kansas.

Forward Looking Statements
This press release contains forward-looking statements within the meaning of applicable securities laws. These statements relate to future events or future performance and reflect management's expectations, estimates, and projections regarding, among other things, Avcon Industries expansion of approved modifications for the Bombardier Challenger 604, 605, and 650 platforms, anticipated customer demand for the certified systems, the continued development and certification of new capabilities across additional platforms, and the expected operational and mission benefits of the STCs described herein. Forward-looking statements are often identified by words such as "may," "will," "expect," "anticipate," "continue," "explore," "extend," or similar expressions.

These statements are based on current expectations and assumptions and are subject to a number of risks and uncertainties that could cause actual results to differ materially from those described in the forward-looking statements, including but not limited to: changes in FAA regulatory requirements or certification timelines; shifts in defense and special mission market demand; the availability of customer aircraft for modification; supply chain and manufacturing constraints; and other factors beyond the company's control. Readers are cautioned not to place undue reliance on forward-looking statements. Avcon Industries, Inc. and Butler National Corporation undertake no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events, or otherwise, except as required by applicable law.

Media Contact
Marcus Abendroth
President – Avcon Industries, Inc.
Email: [email protected]
Phone: +1 (913) 780-9595

Learn more: www.avconindustries.com
Corporate site: www.butlernational.com

SOURCE Avcon Industries, Inc.